Swimmer's Itch

Swimmer's itch, also called cercarial dermatitis, is a
skin rash caused by an
allergic reaction to infection with certain parasites of birds and
mammals. These microscopic parasites
are released from infected snails who swim in fresh and salt water, such as lakes, ponds, and oceans used
for swimming and wading. Infection is found throughout the world.
Swimmer's itch generally occurs during summer months.

What are the signs and symptoms of swimmer's itch?

Within minutes to days after swimming in contaminated
water, you may experience tingling, burning, or itching of the skin.
Small reddish pimples appear
within 12 hours. Pimples may develop into small blisters. Itching may
last up to a week or more, but will gradually go away.

Because
swimmer's itch is caused by an allergic reaction to infection, the more
often you swim or wade in contaminated water, the more likely you are to
develop more serious symptoms. The greater the number of exposures to
contaminated water, the more intense and immediate symptoms of swimmer's
itch will be.